Certain glycine derivatives as factor xa inhibitors for use in the treatment of thrombotic disorders

ABSTRACT

Compounds of formula (I)  
                 
 
     in which R, R 1 , R 2 , n and X 1  have the meanings given in the specification are Factor Xa inhibitors useful in the treatment of thrombotic disorders.

[0001] The present invention relates to compounds useful aspharmaceuticals, to pharmaceutical compositions comprising thecompounds, to a process for preparing the compounds, to intermediatesuseful in the preparation of the compounds, and to use of the compoundsas pharmaceuticals.

[0002] Cardiovascular disease continues to present a major worldwidehealth problem, and is a common cause of serious illness and death.

[0003] One line of investigation being pursued by researchers in thesearch for new treatments for cardiovascular disease is based upon thehypothesis that an inhibitor of the serine protease, Factor Xa, may beuseful as an anticoagulant agent in the treatment of thrombotic disease.

[0004] Inhibitors of Factor Xa are known. For example, WO 99/11657, WO99/11658 and WO 00/76971 disclose certain compounds containing anaromatic group, a glycine residue that bears a cyclic group and alipophilic group.

[0005] WO 99/11657, which discloses compounds in which the aromaticgroup is an aminoisoquinoline group, also generically disclosesaminoisoquinoline compounds containing a glycine residue that bears anacyclic group.

[0006] Surprisingly, compounds containing particular phenyl, indolyl orbenzo[b]thiophene groups, a glycine residue bearing a heteraalkyl groupand a 4-(1-methylpiperidin-4-yl)piperidin-1-yl or4-(1-methylpiperidin-4-yl)piperazin-1-yl group have now been found thatare selective Factor Xa inhibitors and have particularly advantageousproperties.

[0007] Accordingly, the present invention provides a compound of formula(I)

[0008] in which

[0009] X¹ represents CH or N;

[0010] n is 1 or 2;

[0011] each R represents hydrogen or methyl;

[0012] R¹ represents imidazol-1-yl or X^(a)R^(a)

[0013] in which

[0014] X^(a) represents O, S or NR^(b);

[0015] R^(a) represents a hydrogen atom, a (1-4C)alkyl group, a phenylgroup or a pyridyl group;

[0016] R^(b) represents a hydrogen atom, a (1-4C)alkyl group or,together with R^(a) and the nitrogen atom to which they are attachedrepresents a saturated 4 to 6-membered ring which may contain, as a ringmember, one of O, S and NR^(c) in which R^(c) represents hydrogen or(1-4C)alkyl; and

[0017] R² is selected from

[0018] in which

[0019] X² represents a hydrogen atom, a halogen atom or an amino group;

[0020] X³ represents a hydrogen atom, a methyl group, a fluorine atom, achlorine atom or a bromine atom;

[0021] X⁴ represents a hydrogen atom, a methyl group or a halogen atom;

[0022] X⁵ represents a chlorine atom, a methoxy group or a methyl group;and

[0023] X⁶ represents a hydrogen atom, a halogen atom or a methyl group;

[0024] or a pharmaceutically acceptable salt thereof.

[0025] Compounds of formula (I) have been found to be potent andselective inhibitors of the serine protease, Factor Xa, to have goodanticoagulant activity in human plasma, to have good plasma exposureupon oral administration to mammals, and to possess particularlyadvantageous pharmacological and toxicological profiles of activity.

[0026] In the compounds of formula (I), preferably (CHR)_(n) is selectedfrom CH₂, CHCH₃ and CH₂CH₂.

[0027] R¹ preferably represents imidazol-1-yl, hydroxy, (1-4C)alkoxy,(1-4C)alkylthio, di(1-4C)alkylamino, phenylthio, pyridylthio,piperidin-1-yl or morpholino.

[0028] More preferably R¹ represents imidazol-1-yl, hydroxy, methoxy,methylthio, 2-propylthio, dimethylamino, phenylthio, pyrid-2-ylthio,piperidin-1-yl or morpholino.

[0029] Examples of particular values for (CHR)_(n)R₁ areimidazol-1-ylmethyl, hydroxymethyl, 1-hydroxyethyl, methoxymethyl,1-methoxyethyl, methylthiomethyl, prop-2-ylthiomethyl,2-methylthioethyl, N,N-dimethylaminomethyl, phenylthiomethyl,pyrid-2-ylthiomethyl, piperidin-1-ylmethyl and morpholinomethyl.

[0030] In the groups represented by R², X² preferably represents ahydrogen atom or a halogen atom.

[0031] More preferably X² represents a hydrogen atom or a fluorine atom;

[0032] X³ represents a hydrogen atom, a fluorine atom, a chlorine atomor a methyl group;

[0033] X⁴ represents a chlorine atom;

[0034] X⁵ represents a chlorine atom or a methoxy group; and

[0035] X⁶ represents a chlorine atom.

[0036] Particularly preferred values for R² are 4-chlorophenyl,4-methoxyphenyl, 3-fluoro-4-methoxyphenyl, indol-6-yl,3-methylindol-6-yl, 3-chloroindol-6-yl, 5-fluoroindol-2-yl,5-chloroindol-2-yl or 6-chlorobenzo[b]thiophen-2-yl.

[0037] Especial mention may be made of compounds of formula (I) in whichR² is 4-methoxyphenyl, indol-6-yl or 5-chloroindol-2-yl.

[0038] One particular value for X¹ is CH. Another is N.

[0039] As used herein, unless otherwise indicated, the term halogen atomincludes fluorine, chlorine and bromine.

[0040] It will be appreciated that the compounds of formula (I) containa center of asymmetry that has the (D) configuration. The (D)configuration refers to the configuration of the amino acids from whichthe compounds may be prepared. The compounds may therefore exist and beisolated in a mixture with the corresponding (L) isomer, such as aracemic mixture, or separately. Preferably the compounds are isolatedsubstantially free of the (L) isomer.

[0041] It will also be appreciated that the compounds of formula (I) ortheir pharmaceutically acceptable salts may be isolated in the form of asolvate, and accordingly that any such solvate is included within thescope of the present invention.

[0042] The compounds of formula (I) and their pharmaceuticallyacceptable salts may be prepared by a process, which comprises

[0043] (a) reacting a compound of formula (II)

[0044]  or a salt thereof, with a compound of formula (III)

[0045]  or a reactive derivative thereof; or

[0046] (b) reacting a compound of formula (IV)

[0047]  or a salt thereof, with a compound of formula (V)

HOOC—R²  (V)

[0048] or a salt or reactive derivative thereof;

[0049] followed, if a pharmaceutically acceptable salt is desired, byforming a pharmaceutically acceptable salt.

[0050] The reaction between a compound of formula (II) with a compoundof formula (III) may conveniently be performed employing reagents andreaction conditions conventionally used for the formation of an amidebond. The reaction is conveniently carried out in the presence of abenzotriazole-based reagent such as 1-hydroxybenzotriazole or1-hydroxy-7-azabenzotriazole and a dehydrating agent such asdicyclohexylcarbodiimide or1-(3-dimethylaminopropyl)-3-ethylcarbodiimide, in an inert organicsolvent such as dimethylformamide and/or methylene chloride. Thereaction is conveniently conducted at a temperature of from 0 to 50° C.,preferably at ambient temperature. If a salt of a compound of formula(II) is used, the reaction is conveniently performed in the additionalpresence of a base such as triethylamine. Other suitable reagents andsolvents are known in the art, for example an acid halide, such as thechloride in the presence of a base, such as triethylamine.

[0051] The reaction between a compound of formula (IV) with a compoundof formula (V) may conveniently be performed employing reagents andreaction conditions conventionally used for the formation of an amidebond. The reaction is conveniently carried out in the presence of abenzotriazole-based reagent such as 1-hydroxybenzotriazole or1-hydroxy-7-azabenzotriazole and a dehydrating agent such asdicyclohexylcarbodiimide or1-(3-dimethylaminopropyl)-3-ethylcarbodiimide, in an inert organicsolvent such as dimethylformamide and/or methylene chloride. Thereaction is conveniently conducted at a temperature of from 0 to 50° C.,preferably at ambient temperature. If a salt of a compound of formula(IV) is used, the reaction is conveniently performed in the additionalpresence of a base such as triethylamine. Other suitable reagents andsolvents are known in the art, for example an acid halide, such asp-anisoyl chloride in the presence of a base, such as triethylamine.Alternatively, the compound of formula (IV) may be reacted with acompound of formula (V) in the presence of diethylcyanophosphonate. Thisreaction is conveniently performed in an organic solvent such asdichloromethane in the presence of a base, such as triethylamine. Thetemperature is conveniently in the range of from −25 to 25° C.

[0052] The compound of formula (II) in which X¹ is CH is known, forexample from WO 00/76971 at pages 163-164, and is named as4-(1-methylpiperidin-4-yl)piperidine or 1-methyl-4,4′-bispiperidine.

[0053] The compound of formula (II) in which X¹ is N is referred toherein as 1-(1-methylpiperidin-4-yl)piperazine.

[0054] The compounds of formula (III) may be prepared by reacting acompound of formula (VI)

[0055] in which R⁴ represents a carboxyl protecting group, for example a(1-6C)alkyl group, such as methyl or ethyl, with a compound of formula(IV) to afford a compound of formula (VII)

[0056] followed by removing the protecting group.

[0057] The compounds of formula (IV) may be prepared by reacting acompound of formula (II) with a compound of formula (VIII)

[0058] in which R⁵ represents an amino protecting group, such ast-butoxycarbonyl (Boc) to afford a compound of formula (IX)

[0059] followed by removing the protecting group.

[0060] The compounds of formulae (VI) and (VIII) are known or may beprepared using conventional methods for the preparation of amino acidsprotected on the carboxy or amino group. Particular preparations arealso described in the Examples.

[0061] The compounds of formula (V) are well known.

[0062] The protection of amino and carboxylic acid groups is describedin McOmie, Protecting Groups in Organic Chemistry, Plenum Press, NY,1973, and Greene and Wuts, Protecting Groups in Organic Synthesis, 2nd.Ed., John Wiley & Sons, NY, 1991. Examples of carboxy protecting groupsinclude C₁-C₆ alkyl groups such as methyl, ethyl, t-butyl and t-amyl;aryl(C₁-C₄)alkyl groups such as benzyl, 4-nitro-benzyl, 4-methoxybenzyl,3,4-dimethoxybenzyl, 2,4-dimethoxybenzyl, 2,4,6-trimethoxybenzyl,2,4,6-trimethylbenzyl, benzhydryl and trityl; silyl groups such astrimethylsilyl and t-butyldimethylsilyl; and allyl groups such as allyland 1-(trimethylsilylmethyl)prop-1-en-3-yl.

[0063] Examples of amine protecting groups include acyl groups, such asgroups of formula RCO in which R represents C₁₋₆ alkoxy, phenyl C₁₋₆alkoxy, or a C₃₋₁₀ cycloalkoxy, wherein a phenyl group may be optionallysubstituted, for example by one or two of halogen, C₁-C₄ alkyl and C₁-C₄alkoxy.

[0064] Preferred amino protecting groups include benzyloxycarbonyl (CBz)and t-butoxycarbonyl (Boc).

[0065] Certain of the intermediates described herein, for example thecompounds of formulae (III) and (IV), are believed to be novel andaccordingly are provided as further aspects of the invention.

[0066] The compounds of the invention may be administered by anyconvenient route, e.g. into the gastrointestinal tract (e.g. rectally ororally), the nose, lungs, musculature or vasculature or transdermally.The compounds may be administered in any convenient administrative form,e.g. tablets, powders, capsules, solutions, dispersions, suspensions,syrups, sprays, suppositories, gels, emulsions, patches etc. Suchcompositions may contain components conventional in pharmaceuticalpreparations, e.g. diluents, carriers, pH modifiers, sweeteners, bulkingagents, and further active agents. If parenteral administration isdesired, the compositions will be sterile and in a solution orsuspension form suitable for injection or infusion. Such compositionsform a further aspect of the invention.

[0067] Viewed from this aspect the invention provides a pharmaceuticalcomposition, which comprises the compound of formula (I) or apharmaceutically acceptable salt thereof, together with apharmaceutically acceptable diluent or carrier.

[0068] According to another aspect, the present invention provides thecompound of formula (I) or a pharmaceutically acceptable salt thereof,for use in therapy.

[0069] According to another aspect, the present invention provides theuse of the compound of formula (I) or a pharmaceutically acceptable saltthereof, for the manufacture of a medicament for the treatment of athrombotic disorder.

[0070] According to another aspect, the present invention provides amethod of treating a thrombotic disorder in a subject requiringtreatment, which comprises administering an effective amount of acompound of formula (I) or a pharmaceutically acceptable salt thereof.

[0071] The subject may be a human or a non-human animal, such as anon-human mammal, for example a cat, dog, horse, cow or sheep.

[0072] The thrombotic disorder may be, for example, venous thrombosis,pulmonary embolism, arterial thrombosis, myocardial ischaemia,myocardial infarction or cerebral thrombosis. A particular indicationis, for example, prophylaxis of post-operative venous thrombosisfollowing high risk orthopedic surgery (such as hip or kneereplacement), primary treatment of venous thrombosis, secondaryprevention of ischemic cardiovascular complications following myocardialinfarction (in combination with e.g. low dose aspirin), or prevention ofembolic stroke in non-valvular atrial fibrillation. The compounds mayalso be used in accordance with the method of the invention in thetreatment of acute vessel closure associated with thrombolytic therapyand restenosis, for example after transluminal coronary angioplasty orbypass grafting of the coronary or peripheral arteries, and in themaintenance of vascular access patency in long term hemodialysispatients.

[0073] The dosage of the compound of formula (I) will depend upon thenature and severity of the condition being treated, the administrationroute and the size and species of the subject. In general, quantities inthe range of from 0.01 to 100 μM/kg bodyweight will be administered.

[0074] As used herein, the term “treatment” includes prophylactic use.The term “effective amount” refers to the amount of the compound offormula (I) that is effective to reduce or inhibit the development ofthe symptoms of the thrombotic disorder being treated.

[0075] The compound according to the invention may be administered aloneor in combination with an anticoagulant having a different mode ofaction or with a thrombolytic agent.

[0076] The following Examples illustrate the invention. Abbreviationsused follow IUPAC-IUB nomenclature. Additional abbreviations are Boc,tertiary-butyloxycarbonyl; DCC, dicyclohexylcarbodiimide; DIEA,N,N-diisopropylethylamine; DMSO, dimethyl sulfoxide (perdeuterated iffor NMR); DMF, dimethylformamide; EDCI,1-(3-dimethylaminopropyl)-3-ethylcarbodiimide; ES-MS, electrospray massspectrum; EtOAc, ethyl acetate; Et₂O, diethyl ether; HOAt,1-hydroxy-7-aza-benzotriazole; HOBt, 1-hydroxy benzotriazole; HPLC, highpressure liquid chromatography; MeOH, methanol; SCX, strong cationexchange; TEA, triethylamine; TFA, trifluoroacetic acid; and THF,tetrahydrofuran. Reagents were obtained from a variety of commercialsources.

[0077] The following abbreviations are used throughout: Abbreviationsused follow IUPAC-IUB nomenclature. Additional abbreviations are Boc,tertiary-butyloxycarbonyl; CMA, chloroform:methanol: concentratedammonium hydroxide (80:18:2); DEPC, diethyl cyanophosphonate. DCC,dicyclohexylcarbodiimide; DIEA, N,N-diisopropylethylamine; DMSO,dimethyl sulfoxide (perdeuterated if for NMR); DMF, dimethylformamide;EDCI, 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride;ES-MS, electrospray mass spectrum; EtOAc, ethyl acetate; Et₂O, diethylether; HOAt, 1-hydroxy-7-azabenzotriazole; HOBt, 1-hydroxybenzotriazole;HPLC, high pressure liquid chromatography; MeOH, methanol; SCX, strongcation exchange; TEA, triethylamine; TFA, trifluoroacetic acid; and THF,tetrahydrofuran. Reagents were obtained from a variety of commercialsources.

General Lactone Opening Methods

[0078] Method 1: In a manner similar to that described by L. N.Jungheim, et al.; J. Med. Chem. 1996, 39, 96-108, a 0° C. solution ofN-Boc-D-serine β-lactone (1 eq; prepared according to Marinez, E. R.;Salmassian, E. K.; Lau, T. T.; Gutierrez, C. G. J. Org. Chem. 1996, 61,3548-3550) in THF (0.3 M) is treated with a sodium thioalkoxide (1.1eq). After stirring for 30 min, the reaction mixture is allowed to warmto room temperature and stir for an additional 2-3 h, before it isacidified with 10% aqueous sodium bisulfate solution. The aqueous layeris extracted with ethyl acetate twice, and the combined organic layersare dried over Na₂SO₄, filtered and concentrated in vacuo. The cruderesidue is purified by chromatography over silica gel, eluting with amixture of 1 to 2% methanol in dichloromethane with 0.5% acetic acid.The product-containing fractions are then combined and concentrated invacuo.

[0079] Method 2: In a manner similar to that described by Ratemi, E. S.;Vederas, J. C. Tetrahedron Lett. 1994, 35, 7605-7608, a solution of anN-trimethylsilylamine (1.3 eq) in acetonitrile (0.3 M) is treated with asolution of N-Boc-D-serine β-lactone (1 eq) in acetonitrile (0.1 M).After stirring for 3 h, the reaction mixture is concentrated in vacuo.The crude residue is dissolved in 3:1 methanol/THF (0.05 to 0.1 M) andtreated with 10% w/v aqueous potassium carbonate solution (approximately25% of the organic solvent volume). After stirring for 1.5 h, thereaction mixture is concentrated in vacuo; and the resulting solid istriturated with dichloromethane containing a small amount of methanol.The organic filtrate is concentrated in vacuo to give the potassium saltof the acid, which is used without further purification.

General Coupling Methods

[0080] Method 1: A solution or suspension of an amine, aminehydrochloride salt or amine hydrobromide salt (1 eq, approximately 0.1to 0.2 M) in THF, dichloromethane, or DMF (or a mixture of any of thesesolvents) is treated with either a carboxylic acid (approximately 1 eq)or a carboxylic acid potassium salt, either HOBt or HOAt (approximately1 eq), either TEA or DIEA (0-5 eq), and either EDCI or DCC(approximately 1 eq). After stirring overnight at room temperature, thereaction mixture is washed with saturated aqueous sodium bicarbonatesolution. The aqueous layer is extracted twice with ethyl acetate ordichloromethane. The combined organic layers are then dried with MgSO₄or Na₂SO₄, filtered and concentrated in vacuo. If necessary, the productis purified by chromatography over silica gel, eluting with a gradientof 0% through 5 to 15% 2 N ammonia/methanol in dichloromethane. Theproduct-containing fractions are then combined and concentrated invacuo. Alternatively, the product can be purified by reverse phase HPLCon C-18 using a 5 to 95% gradient of acetonitrile in H₂O with 0.01% HCl.The product-containing fractions are then combined and freeze-dried.

[0081] Method 2: To a stirring solution of an amine or aminehydrochloride salt (1 eq), triethylamine (1-3 eq), and a carboxylic acid(about 1.2 eq) in dichloromethane (0.2-0.5M) at 0° C., is slowly addeddiethyl cyanophosphonate (about 1.2 eq). After stirring overnight, thesolvents are removed in vacuo and the residue is partitioned between anorganic solvent such as ethyl acetate or dichloromethane and washed withsaturated aq. NaHCO₃, followed by brine. The organic phase is then driedwith MgSO₄ or Na₂SO₄, filtered and concentrated in vacuo. If necessary,the product is purified by chromatography over silica gel, eluting witha gradient of 0-10% 2 N ammonia/methanol in either dichloromethane orchloroform. The product-containing fractions are then combined andconcentrated in vacuo.

[0082] Method 3: The amine or amine hydrochloride salt (1 eq) andtriethylamine (1-3 eq) are dissolved in dichloromethane (0.1-0.5 M) andan acid chloride (about 1.2 eq) is added. After stirring overnight, thereaction mixture is quenched with saturated NaHCO₃ solution. The aqueouslayer is extracted twice with dichloromethane, and the combined organiclayers are dried over Na₂SO₄, filtered and concentrated in vacuo. Ifnecessary, the product can be purified by chromatography over silicagel, eluting with a gradient of 0% through 5 to 10% 2 N ammonia/methanolin dichloromethane. The product-containing fractions are then combinedand concentrated in vacuo. Alternatively, the crude product can bepurified by reverse phase HPLC using a 5 to 95% gradient of 0.01%HCl/H₂O in acetonitrile. The product-containing fractions are thencombined and freeze-dried.

[0083] Method 4: A solution or suspension of an amine or aminehydrochloride salt (1 eq, approximately 0.2 M) in THF, dichloromethane,or DMF (or a mixture of any of these solvents) is treated with acarboxylic acid (approximately 1 eq), and either TEA or DIEA (0-3 eq)and mixed several minutes. Either HOBt or HOAt (approximately 1 eq) andeither EDCI or DCC (approximately 1 eq) are separately stirred togetherin a solvent; and the resulting mixture is added to the other solution,or vice versa. After stirring overnight at room temperature, thesolvents may be removed; and then the mixture is diluted with an organicsolvent (such as ethyl acetate or dichloromethane) and washed withsaturated aqueous sodium bicarbonate followed by brine. The organicsolution is then dried with MgSO₄, filtered and concentrated in vacuo.When DCC is used as the coupling reagent, after stirring overnight atroom temperature, the mixture may be filtered to remove dicyclohexylurea, and then purified by SCX chromatography as described below.

[0084] If necessary, the product may be then purified by chromatographyover silica gel, eluting with a gradient of 0% through 2 to 12% 2 Nammonia/methanol in dichloromethane or chloroform. Theproduct-containing fractions are then combined and concentrated invacuo.

General Deprotection Methods

[0085] Method 1 (t-butyl carbamate): A solution of the t-butyl carbamate(1 eq) in CH₂Cl₂ (0.2 M) is treated with anisole (5 eq) and TFA (20% byvolume). After stirring 1 to 3 h at ambient temperature, the reactionmixture is concentrated in vacuo. The crude residue is purified bystrong cation exchange (SCX) chromatography. The SCX column is washedwith a 5% solution of acetic acid in methanol and the TFA salt isdissolved in methanol (possibly with a cosolvent such asdichloromethane) and loaded onto the SCX column. The column is thenwashed with methanol (possibly with a cosolvent such as dichloromethane)and then the free base is eluted from the column with a 2 N solution ofammonia or triethylamine in methanol (possibly with a cosolvent such asdichloromethane). The product containing fractions are then combined andconcentrated in vacuo to give the product in the free base form.

[0086] Method 2 (t-butyl carbamate): HCl gas is bubbled into a solutionof the t-butyl carbamate in anhydrous MeOH (0.1 M) for approximately 10to 30 min, then the reaction mixture is concentrated in vacuo.

[0087] Method 3: A solution of the benzyl carbamate and 10% Pd/C (15%w/w) in anhydrous EtOH (0.1 M) is subjected to an atmosphere of H₂ atroom temperature and pressure and allowed to stir overnight. Thereaction mixture is filtered over diatomaceous earth, and the filtrateis concentrated in vacuo.

General HCl Salt Formation Methods

[0088] Method 1: The free base is dissolved in 0.2 N aqueous HCl (1-2 eqof HCl). The resulting solution is freeze-dried to give the aminehydrochloride salt.

[0089] Method 2: A solution of the free base in a small amount ofdichloromethane is treated with 1.0-2.2 equivalents of 1 M HCl in ether.After stirring about 30 min, the reaction mixture is filtered; and theresulting solid is rinsed with ether and dried to give the aminehydrochloride salt.

[0090] Method 3: A solution of the free base in a small amount of MeOHis treated with a 0.5 M solution of ammonium chloride in MeOH (1 eq).The resulting solution is concentrated in vacuo to give the aminehydrochloride salt.

General Analytical HPLC Methods

[0091] Method 1: Vydac C18 (4.6×250 mm) or Symmetry (4.6×150 mm), elutewith a linear gradient of 90/10 through 50/50 (0.1% TFA in water/0.1%TFA in acetonitrile) over 45 min, 1 mL/min, λ=214 nm.

[0092] Method 2: Xterra RP18 4.6×150 mm column, gradient of 10-50% CH₃CNin H₂O with 0.1% TFA, 1 mL/min, over 40 min, Waters 996 PDA and/or SedexELS detection.

[0093] Method 3: Xterra RP18 4.6×50 mm column, gradient of 2-50% CH₃CNin H₂O with 0.1% TFA, 1 mL/min, over 30 min, λ=214 nm.

[0094] Method 4: Xterra RP18 4.6×50 mm column, gradient of 2-70% CH₃CNin H₂O with 0.1% TFA, 1 mL/min, over 30 min, λ=214 nm.

Preparations of Amino Acid Intermediates

[0095] N-Boc-O-Methyl-D-threonine Methyl Ester.

[0096] Prepared using methods similar to those described in Andurkar, S.V.; Stables, S. P.; Kohn. H. Tetrahedron Asymm., 1998, 9(21), 3841-3854.To a solution of N-Boc-D-threonine (36.5 mmol) in acetonitrile (500 mL)protected from external light, is added Ag₂O (182.5 mmol) and CH₃I(365.0 mmol). After stirring for 3-4 days, the mixture is filteredthrough diatomaceous earth and concentrated in vacuo. The residue isthen chromatographed over silica gel, eluting with a gradient of 0%ethyl acetate in hexanes through 100% ethyl acetate in hexanes. Theproduct containing fractions are combined and concentrated to give 4.78g (52.9%) of the title compound.

[0097]¹H NMR.

[0098] Analysis for C₁₁H₂₁NO₅.0.1H₂O: Calcd: C 52.41; H 8.40; N 5.56;Found: C 52.44; H 7.89; N 5.70.

[0099] N-Boc-O-Methyl-D-allo-threonine Methyl Ester.

[0100] Prepared from N-Boc-D-allo-threonine using methods substantiallyequivalent to those described above for the preparation ofN-Boc-O-methyl-D-threonine methyl ester.

[0101] (70%).

[0102]¹H NMR.

[0103] ES-MS m/z 248.0 (M+1)⁺.

[0104] N-Boc-O-Methyl-D-threonine.

[0105] To a solution of N-Boc-O-methyl-D-threonine methyl ester (8.09mmol) in 1,4-dioxane (10 mL) is added a solution of LiOH (24.3 mmol) inwater (20 mL). After stirring for 2-3 h, the solvents are removed invacuo and the residue partitioned between water and ether. The aqueouslayer is acidified with solid citric acid to approximately pH 3, thenextracted with ethyl acetate. The ethyl acetate extract is washed withwater, dried with MgSO₄, filtered and concentrated in vacuo to yield1.70 g (90%) of the title compound.

[0106]¹H NMR.

[0107] Analysis for C₁₀H₁₉NO₅.0.1H₂O: Calcd: C 50.45; H 8.05; N 5.88;Found: C 50.67; H 8.01; N 5.73.

[0108] N-Boc-O-Methyl-D-allo-threonine.

[0109] Prepared from N-Boc-O-methyl-D-allo-threonine methyl ester usingmethods substantially equivalent to those described above for thepreparation of N-Boc-O-methyl-D-threonine (99%).

[0110]¹H NMR.

[0111] Analysis for C₁₀H₁₉NO₅.0.14H₂O: Calcd: C 50.05; H 7.98; N 5.84;Found: C 49.64; H 7.67; N 5.81.

[0112] N-Boc-D-allo-Threonine.

[0113] Prepared from D-allo-threonine using methods substantiallyequivalent to those described in Shuman, R. T.; Ornstein, P. L.;Paschal, J. W.; Geselchen, P. D., J. Org. Chem, 1990, 55, 738-741.

[0114]¹H NMR.

[0115] ES-MS m/z 218.2 (M−1)⁻.

Preparation of Compounds of Formula (IX), X¹═CH

[0116] 1-(N-Boc-D-Serinyl)-4-(1-methylpiperidin-4-yl)piperidine.

[0117] Prepared from Boc-D-serine and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide (WO 00/76971) usingmethods substantially equivalent to General Coupling Method 1.

[0118]¹H NMR.

[0119] ES-MS, m/z 370.3 (M+1)⁺.

[0120] Analysis For C₁₉H₃₅N₃O₄.0.3.H₂O: Calcd: C 60.87; H 9.57; N 11.21;Found: C 60.87; H 9.37; N 11.19.

[0121]1-(N-Cbz-O-Methyl-D-serinyl)-4-(1-methylpiperidin-4-yl)-piperidine.

[0122] Prepared from N-Cbz-O-methyl-D-serine (Andurkar, S. V.; Stables,J. P.; Kohn, H.; Tetrahedron: Asymm, 1998, 9 (21), 3841-3854) and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 1.

[0123]¹H NMR.

[0124] ES-MS, m/z 418.3 (M+1)⁺.

[0125] Analysis For C₂₃H₃₅N₃O₄.0.2H₂O: Calcd: C 65.59; H 8.47; N 9.98.Found: C 65.61; H 8.57; N 9.65.

[0126] 1-(N-Boc-D-Threoninyl)-4-(1-methylpiperidin-4-yl)piperidine.

[0127] Prepared from Boc-D-threonine and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 4.

[0128] ES-MS, m/z 384.3 (M+1)⁺.

[0129]1-(N-Boc-D-allo-Threoninyl)-4-(1-methylpiperidin-4-yl)-piperidine.

[0130] Prepared from N-Boc-D-allo-threonine and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 1.

[0131]¹H NMR.

[0132] ES-MS, m/z 384.5 (M+1)⁺.

[0133] Analysis for C₂₀H₃₇N₃O₄.0.2H₂O: Calcd: C 60.73; H 9.43; N 10.62;Found: C 60.54; H 9.54; N 11.75.

[0134]1-(N-Boc-O-Methyl-D-threoninyl)-4-(1-methylpiperidin-4-yl)-piperidine.

[0135] Prepared from N-Boc-D-methyl-D-threonine and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 4.

[0136]¹H NMR.

[0137] ES-MS, m/z 398.4(M+1)⁺.

[0138] Analysis for C₂₁H₃₉N₃O₄.H₂O: Calcd: C 60.69; H 9.95; N 10.11;Found: C 60.55; H 9.55; N 11.21.

[0139] 1(N-Boc-D-Methioninyl)-4-(1-methylpiperidin-4-yl)-piperidine.

[0140] Prepared from N-Boc-D-methionine and4-(1-methyl-piperidin-4-yl)piperidinedihydrobromide using methodssubstantially equivalent to General Coupling Method 1.

[0141]¹H NMR.

[0142] ES-MS, m/z 414.3 (M+1)⁺.

[0143] Analysis for C₂₁H₃₉N₃O₃S.0.3H₂O: Calcd: C 57.00; H 8.88; N 9.50;Found: C 57.34; H 8.89; N 8.81.

[0144]1-(N-Boc-S-Phenyl-D-cysteinyl)-4-(1-methylpiperidin-4-yl)-piperidine.

[0145] Prepared from N-Boc-S-phenyl-D-cysteine (L. N. Jungheim, et al.;J. Med. Chem. 1996, 39, 96-108) and 4-(1-methylpiperidin-4-yl)piperidinedihydrobromide using methods substantially equivalent to GeneralCoupling Method 1.

[0146]¹H NMR.

[0147] ES-MS, m/z 462.3 (M+1)⁺.

[0148] Analysis for C₂₅H₃₉N₃O₃S.1.2H₂O: Calcd: C 62.13; H 8.63; N 8.70.Found: C 62.05; H 8.32; N 8.75.

[0149]1-[N-Boc-S-(2-Pyridyl)-D-cysteinyl]-4-(1-methylpiperidin-4-yl)piperidine.

[0150] Prepared from N-Boc-S-(2-pyridyl)-D-cysteine (L. N. Jungheim, etal.; J. Med. Chem. 1996, 39, 96-108) and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 1.

[0151]¹H NMR.

[0152] ES-MS, m/z 463.3 (M+1)⁺.

[0153] Analysis for C₂₄H₃₈N₄O₃S.0.7H₂O: Calcd: C 60.65; H 8.36; N 11.79;Found: C 60.95; H 8.02; N 11.07.

[0154]1-[N-Boc-S-(2-Propyl)-D-cysteinyl]-4-(1-methylpiperidin-4-yl)piperidine.

[0155] Prepared from N-Boc-S-(2-propyl)-D-cysteine and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 1.N-Boc-S-(2-propyl)-D-cysteine is prepared from Boc-D-serine β-lactoneand sodium 2-propanethiolate using methods substantially equivalent toGeneral Lactone Opening Method 1.

[0156]¹H NMR.

[0157] ES-MS, m/z 428.3 (M+1)⁺.

[0158] Analysis for C₂₂H₄₁N₃O₃S.H₂O: Calcd: C 59.29; H 9.73; N 9.43;Found: C 58.95; H 9.38; N 9.21.

[0159]1-(N-Boc-S-Methyl-D-cysteinyl)-4-(1-methylpiperidin-4-yl)-piperidine.

[0160] Prepared from N-Boc-S-methyl-D-cysteine and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 1.N-Boc-S-methyl-D-cysteine is prepared from Boc-D-serine β-lactone andsodium thiomethoxide using methods substantially equivalent to GeneralLactone Opening Method 1.

[0161]¹H NMR.

[0162] ES-MS, m/z 400.3 (M+1)⁺.

[0163] Analysis for C₂₀H₃₇N₃O₃S.1.2H₂O: Calcd: C 57.03; H 9.43; N 9.98;Found: C 57.03; H 8.85; N 9.92.

[0164]1-[N-Boc-β-(4-Morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidine.

[0165] Prepared from N-Boc-β-(4-morpholinyl)-D-alanine potassium saltand 4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 1.N-Boc-β-(4-morpholinyl)-D-alanine potassium salt is prepared fromBoc-D-serine β-lactone and N-trimethylsilylmorpholine using methodssubstantially equivalent to General Lactone Opening Method 2.

[0166]¹H NMR.

[0167] ES-MS, m/z 439.3 (M+1)⁺.

[0168] 1-(N-Boc-β-Dimethylamino-D-alaninyl)-4-(1-methylpiperidin-4-yl)piperidine.

[0169] Prepared from N-Boc-β-dimethylamino-D-alanine, potassium salt and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 1.N-Boc-β-dimethylamino-D-alanine potassium salt is prepared fromBoc-D-serine β-lactone and N,N-dimethyltrimethylsilylamine using methodssubstantially equivalent to General Lactone Opening Method 2.

[0170]¹H NMR.

[0171] ES-MS, m/z 397.3 (M+1)⁺.

[0172] Analysis for C₂₁H₄₀N₄O₃: Calcd: C 63.60; H 10.17; N 14.13; Found:C 63.84; H 9.82; N 13.27.

[0173]1-[N-Boc-β-(1-Imidazolyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidine.

[0174] Prepared from N-Boc-β-(1-imidazolyl)-D-alanine potassium salt and4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 1.N-Boc-β-(1-imidazolyl)-D-alanine potassium salt is prepared fromBoc-D-serine β-lactone and 1-(trimethylsilyl)imidazole using methodssubstantially equivalent to General Lactone Opening Method 2.

[0175]¹H NMR.

[0176] ES-MS, m/z 420.3 (M+1)⁺.

[0177] Analysis for C₂₂H₃₇N₅O₃.0.4H₂O: Calcd: C 61.91; H 8.93; N 16.41;Found: C 62.01; H 8.49; N 15.80.

[0178] 1-[N-Boc-β-(1-Piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidine.

[0179] Prepared from N-Boc-β-(1-piperidinyl)-D-alanine potassium saltand 4-(1-methylpiperidin-4-yl)piperidine dihydrobromide using methodssubstantially equivalent to General Coupling Method 1.N-Boc-β-(1-piperidinyl)-D-alanine potassium salt is prepared fromBoc-D-serine β-lactone and 1-(trimethylsilyl)piperidine using methodssubstantially equivalent to General Lactone Opening Method 2.

[0180]¹H NMR.

[0181] ES-MS, m/z 437.4 (M+1)⁺.

Preparation of Compounds of Formula (IV), X¹═CH

[0182] 1-(D-Serinyl)-4-(1-methylpiperidin-4-yl)piperidineDihydrochloride.

[0183] Prepared from1-(N-Boc-D-serinyl)-4-(1-methylpiperidin-4-yl)piperidine using methodssubstantially equivalent to those described in General DeprotectionMethod 2.

[0184]¹H NMR.

[0185] ES-MS, m/z 270.2 (M+1)⁺.

[0186] Analysis for C₁₄H₂₇N₃O₂.2.0 HCl.2.8H₂O: Calcd: C 42.81; H 8.88; N10.70; Found: C 43.15; H 9.13; N 10.13.

[0187] 1-(O-Methyl-D-serinyl)-4-(1-methylpiperidin-4-yl)piperidine.

[0188] Prepared from1-(N-Cbz-O-methyl-D-serinyl)-4-(1-methyl-piperidin-4-yl)piperidine usingmethods substantially equivalent to those described in GeneralDeprotection Method 3.

[0189]¹H NMR.

[0190] ES-MS, m/z 284.2 (M+1)⁺.

[0191] Analysis for C₁₅H₂₉N₃O₂.0.1 C₂H₅OH.0.7H₂O: Calcd: C 60.73; H10.39; N 13.98; Found: C 60.57; H 9.89; N 13.73.

[0192] 1-(D-Threoninyl)-4-(1-methylpiperidin-4-yl)piperidine.

[0193] Prepared from1-(N-Boc-D-threoninyl)-4-(1-methyl-piperidin-4-yl)piperidine usingmethods substantially equivalent to those described in GeneralDeprotection Method 1. No data.

[0194] 1-(D-allo-Threoninyl)-4-(1-methylpiperidin-4-yl)piperidinehydrochloride.

[0195] Prepared from1-(N-Boc-D-allo-threoninyl)-4-(1-methyl-piperidin-4-yl)piperidine usingmethods substantially equivalent to those described in GeneralDeprotection Method 2.

[0196]¹H NMR.

[0197] ES-MS, m/z 284.5 (M+1)⁺.

[0198] Analysis For C₁₅H₂₉N₃O₂.2.3 HCl.2.4H₂O: Calcd: C 43.89; H 8.86; N10.24 Cl 19.87; Found: C 43.46; H 8.70; N 10.67 Cl 19.61.

[0199] 1(O-Methyl-D-threoninyl)-4-(1-methylpiperidin-4-yl)-piperidine.

[0200] Prepared from1-(N-Boc-O-methyl-D-threoninyl)-4-(1-methylpiperidin-4-yl)piperidineusing methods substantially equivalent to those described in GeneralDeprotection Method 1.

[0201] ES-MS, m/z 298.1 (M+1)⁺.

[0202] 1(D-Methioninyl)-4-(1-methylpiperidin-4-yl)piperidine.

[0203] Prepared from1-(N-Boc-D-methioninyl)-4-(1-methyl-piperidin-4-yl)piperidine usingmethods substantially equivalent to those described in GeneralDeprotection Method 1.

[0204]¹H NMR.

[0205] ES-MS, m/z 314.2 (M+1)⁺.

[0206] 1-(S-Phenyl-D-cysteinyl)-4-(1-methylpiperidin-4-yl)-piperidineDihydrochloride.

[0207] Prepared from1-(N-Boc-S-phenyl-D-cysteinyl)-4-(1-methylpiperidin-4-yl)piperidineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0208]¹H NMR.

[0209] ES-MS, m/z 362.2 (M+1)⁺.

[0210] Analysis for C₂₀H₃₁N₃OS.1.7 HCl.1.7H₂O: Calcd: C 52.89; H 8.01; N9.25; Found: C 52.96; H 8.41; N 9.23.

[0211]1-[S-(2-Pyridyl)-D-cysteinyl]-4-(1-methylpiperidin-4-yl)-piperidineDihydrochloride.

[0212] Prepared from1-[N-Boc-S-(2-pyridyl)-D-cysteinyl]-4-(1-methylpiperidin-4-yl)piperidineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0213]¹H NMR.

[0214] ES-MS, m/z 363.2 (M+1)⁺.

[0215] Analysis for C₁₉H₃₀N₄OS.1.9 HCl.5.0H₂O: Calcd: C 43.73; H 8.09; N10.74; Found: C 43.67; H 8.14; N 10.70.

[0216]1-[S-(2-Propyl)-D-cysteinyl]-4-(1-methylpiperidin-4-yl)-piperidineDihydrochloride.

[0217] Prepared from1-[N-Boc-S-(2-propyl)-D-cysteinyl-4-(1-methylpiperidin-4-yl)piperidineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0218]¹H NMR.

[0219] ES-MS, m/z 328.2 (M+1)⁺.

[0220] Analysis for C₁₇H₃₃N₃OS.1.7 HCl.1.9H₂O: Calcd: C 48.18; H 9.16; N9.92; Found: C 48.18; H 9.47; N 9.82.

[0221] 1-(S-Methyl-D-cysteinyl)-4-(1-methylpiperidin-4-yl)-piperidineDihydrochloride.

[0222] Prepared from1-(N-Boc-S-methyl-D-cysteinyl)-4-(1-methylpiperidin-4-yl)piperidineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0223]¹H NMR.

[0224] ES-MS, m/z 300.2 (M+1)⁺.

[0225] Analysis For C₁₅H₂₉N₃OS.1.8 HCl.1.8H₂O: Calcd: C 45.32; H 8.72; N10.57. Found: C 45.38; H 9.07; N 10.41.

[0226]1-[β-(4-Morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)-piperidineTrihydrochloride.

[0227] Prepared from1-[N-Boc-β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0228]¹H NMR.

[0229] ES-MS, m/z 339.3 (M+1)⁺.

[0230] Analysis for C₁₈H₃₄N₄O₂.3.0 HCl.1.3H₂O: Calcd: C 45.87; H 8.47; N11.89; Found: C 45.80; H 8.08; N 11.84.

[0231]1[β-Dimethylamino-D-alaninyl]-4-(1-methylpiperidin-4-yl)-piperidineHydrochloride.

[0232] Prepared from1-(N-Boc-β-dimethylamino-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0233]¹H NMR.

[0234] ES-MS, m/z 297.3 (M+1)⁺.

[0235]1-[β-(1-Imidazolyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)-piperidineHydrochloride.

[0236] Prepared from1-[N-Boc-β-(1-Imidazolyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0237]¹H NMR.

[0238] ES-MS, m/z 320.2 (M+1)⁺.

[0239]1-[β-(1-Piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)-piperidineHydrochloride.

[0240] Prepared from1-[N-Boc-β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0241]¹H NMR.

[0242] ES-MS, m/z 337.3 (M+1)⁺.

EXAMPLES X¹═CH Example 1

[0243]1-[N-(Indole-6-carbonyl)-D-serinyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0244] Prepared from 1-(D-serinyl)-4-(1-methylpiperidin-4-yl)-piperidineand indole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling 4. The HCl salt is prepared following General SaltFormation Method 2.

[0245]¹H NMR.

[0246] ES-MS, m/z 413.2(M+1)⁺; 411.2 (M−1)⁻.

[0247] Analysis for C₂₃H₃₂N₄O₃.1.2 HCl.1.6H₂O: Calcd: C 56.95; H 7.56; N11.55; Cl 8.77; Found: C 57.23; H 7.57; N 11.15; Cl 8.74.

[0248] Analytical HPLC (Method 1): >99%, t_(r)=14.1 min.

Example 2

[0249]1-[N-(5-Chloroindole-2-carbonyl)-D-serinyl]-4-(1-methyl-piperidin-4-yl)piperidineHydrochloride.

[0250] Prepared from 1-(D-serinyl)-4-(1-methylpiperidin-4-yl)-piperidinedihydrochloride and 5-chloroindole-2-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following General Salt Formation Method 1.

[0251]¹H NMR.

[0252] ES-MS, m/z 447.2 (M+1)⁺.

[0253] Analysis for C₂₃H₃₁N₄O₃Cl.1.1 HCl.1.6H₂O: Calcd: C 53.54; H 6.90;N 10.86; Cl 14.43; Found: C 53.61; H 6.44; N 10.82; Cl 14.09.

[0254] Analytical HPLC (Method 4): >99%, t_(r)=12.1 min.

Example 3

[0255]1-[N-(3-Chloroindole-6-carbonyl)-D-serinyl]-4-(1-methyl-piperidin-4-yl)piperidineHydrochloride.

[0256] Prepared from 1-(D-serinyl)-4-(1-methylpiperidin-4-yl)-piperidinedihydrochloride and 3-chloroindole-6-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following General Salt Formation Method 1.

[0257]¹H NMR.

[0258] ES-MS, m/z 447.2 (M+1)⁺.

[0259] Analysis for C₂₃H₃₁N₄O₃Cl 1.1 HCl 1.9H₂O: Calcd: C 52.99; H 6.94;N 10.75; Cl 14.28; Found: C 53.00; H 6.60; N 11.05; Cl 13.94.

[0260] Analytical HPLC (Method 4): >99%, t_(r)=11.5 min.

Example 4

[0261]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-D-serinyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0262] Prepared from 1-(D-serinyl)-4-(1-methylpiperidin-4-yl)-piperidinedihydrochloride and 6-chlorobenzo[b]thiophene-2-carboxylic acid usingmethods substantially equivalent to General Coupling Method 1. The HClsalt is prepared following General Salt Formation Method 1.

[0263]¹H NMR.

[0264] ES-MS, m/z 464.2 (M+1)⁺.

[0265] Analysis for C₂₃H₃₀N₃O₃SCl.1.3 HCl.0.6H₂O: Calcd: C 52.90; H6.27; N 8.05; Cl 15.65; Found: C 52.94; H 6.27; N 8.08; Cl 15.48.

[0266] Analytical HPLC (Method 3): >99%, t_(r)=19.9 min.

Example 5

[0267]1-[N-(Indole-6-carbonyl)-O-methyl-D-serinyl]-4-(1-methyl-piperidin-4-yl)piperidineHydrochloride.

[0268] Prepared from1-(O-methyl-D-serinyl)-4-(1-methyl-piperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 1.

[0269]¹H NMR.

[0270] ES-MS, m/z 427.3 (M+1)⁺.

[0271] Analysis for C₂₄H₃₄N₄O₃.1.0 HCl.1.8H₂O: Calcd: C 58.18; H 7.85; N11.31; Cl 7.16; Found: C 58.20; H 7.89; N 11.38; Cl 7.12.

[0272] Analytical HPLC (Method 3): >98%, t_(r)=15.9 min.

Example 6

[0273]1-[N-(Indole-6-carbonyl)-D-threoninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0274] Prepared from1-(D-threoninyl)-4-(1-methylpiperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling 4. The HCl salt is prepared following General SaltFormation Method 2.

[0275]¹H NMR.

[0276] ES-MS, m/z 427.4(M+1)⁺; 425.3 (M−1)⁻.

[0277] Analysis for C₂₄H₃₄N₄O₃.0.85 HCl.1.4H₂O: Calcd: C 58.17; H 7.49;N 11.31; Cl 6.08; Found: C 58.53; H 7.94; N 10.77; Cl 6.46.

[0278] Analytical HPLC (Method 1): 98%, t_(r)=15.2 min.

Example 7

[0279]1-[N-(Indole-6-carbonyl)-D-allo-threoninyl]-4-(1-methyl-piperidin-4-yl)piperidineHydrochloride.

[0280] Prepared from1-(D-allo-threoninyl)-4-(1-methyl-piperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 2.

[0281]¹H NMR.

[0282] ES-MS, m/z 427.5(M+1)⁺; 425.5 (M−1)⁻.

[0283] Analysis for C₂₄H₃₄N₄O₃.1.7 HCl4.0H₂O: Calcd: C 51.42; H 7.86; N10.00; Cl 10.75; Found: C 51.04; H 8.11; N 12.20; Cl 10.71.

[0284] Analytical HPLC (Method 1): >98%, t_(r)=13.3 min.

Example 8

[0285]1-[N-(5-Chloroindole-2-carbonyl)-D-allo-threoninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0286] Prepared from1-(D-allo-threoninyl)-4-(1-methyl-piperidin-4-yl)piperidinehydrochloride and 5-chloroindole-2-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following Salt Formation Method 2.

[0287]¹H NMR.

[0288] ES-MS, m/z 461.5 (M+1)⁺; 459.4 (M−1)⁻.

[0289] Analysis for C₂₄H₃₇ClN₄O₃.0.95 HCl.1.0H₂O: Calcd: C 54.60; H6.68; N 10.61; Cl 13.10; Found: C 55.15; H 6.78; N 10.68; Cl 13.42.

[0290] Analytical HPLC (Method 1): >98%, t_(r)=22.2 min.

Example 9

[0291]1-[N-(Indole-6-carbonyl)-O-methyl-D-threoninyl]-4-(1-methyl-piperidin-4-yl)piperidineHydrochloride.

[0292] Prepared from1-(O-methyl-D-threoninyl)-4-(1-methyl-piperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 2. The HCl salt is prepared following GeneralSalt Formation Method 2.

[0293]¹H NMR.

[0294] ES-MS, m/z 441.5(M+1)⁺; 439.5 (M−1)⁻.

[0295] Analysis for C₂₅H₃₆N₄O₃.1.6 HCl1.7H₂O: Calcd: C 56.70; H 7.80; N10.58; Cl 10.71; Found: C 56.81; H 8.18; N 10.17; Cl 10.77.

[0296] Analytical HPLC (Method 1): >98%, t_(r)=18.8 min.

Example 10

[0297]1-[N-(4-Methoxybenzoyl)-O-methyl-D-threoninyl]-4-(1-methyl-piperidin-4-yl)piperidineHydrochloride.

[0298] Prepared from1-(O-methyl-D-threoninyl)-4-(1-methyl-piperidin-4-yl)piperidine and4-methoxybenzoic acid using methods substantially equivalent to GeneralCoupling Method 2. The HCl salt is prepared following General SaltFormation Method 2.

[0299]¹H NMR.

[0300] ES-MS, m/z 432.5 (M+1)⁺; 430.5 (M−1)⁻.

[0301] Analysis for C₂₄H₃₇N₃O₄.1.5 HCl-3.5H₂O: Calcd: C 52.48; H 8.35; N7.65; Cl 9.68; Found: C 52.26; H 8.24; N 7.62; Cl 9.77.

[0302] Analytical HPLC (Method 1): >99%, t_(r)=17.4 min.

Example 11

[0303]1-[N-(Indole-6-carbonyl)-D-methioninyl]-4-(1-methyl-piperidin-4-yl)piperidineHydrochloride.

[0304] Prepared from1-(D-methioninyl)-4-(1-methylpiperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling 4. The HCl salt is prepared following General SaltFormation Method 1.

[0305]¹H NMR.

[0306] ES-MS, m/z 457.3(M+1)⁺; 455.4 (M−1)⁻.

[0307] Analysis for C₂₅H₃₆N₄O₂.1.4 HCl0.75H₂O: Calcd: C 58.88; H 7.84; N10.99; Cl 9.73; Found: C 58.49; H 7.48; N 10.86; Cl 9.57.

[0308] Analytical HPLC (Method 1): >93%, t_(r)=22.4 min.

Example 12

[0309]1-[N-(4-Methoxybenzoyl)-D-methioninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0310] Prepared from1-(D-methioninyl)-4-(1-methylpiperidin-4-yl)piperidine hydrochloride and4-methoxybenzoic acid using methods substantially equivalent to GeneralCoupling Method 4. The HCl salt is prepared following General SaltFormation Method 2.

[0311]¹H NMR.

[0312] FD+, m/z 447.4 (M+1)⁺.

[0313] Analysis For C₂₄H₃₇N₃O₃S.1.1 HCl0.9H₂O: Calcd: C 56.11; H 7.69; N8.18; Cl 6.2; Found: C 56.56; H 7.77; N 8.27; Cl 6.43.

[0314] Analytical HPLC (Method 1): 98%, t_(r)=19.9 min.

Example 13

[0315]1-[N-(Indole-6-carbonyl)-S-phenyl-D-cysteinyl]-4-(1-methyl-piperidin-4-yl)piperidineHydrochloride.

[0316] Prepared from1-(S-phenyl-D-cysteinyl)-4-(1-methyl-piperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 3.

[0317]¹H NMR.

[0318] ES-MS, m/z 505.3 (M+1)⁺.

[0319] Analysis for C₂₉H₃₆N₄O₂S.1.0 HCl-0.6H₂O: Calcd: C 63.10; H 6.98;N 10.15; Cl 6.42; Found: C 63.14; H 6.94; N 10.06; Cl 6.23.

[0320] Analytical HPLC (Method 2): >97%, t_(r)=27.4 min.

Example 14

[0321]1-[N-(Indole-6-carbonyl)-S-(2-pyridyl)-D-cysteinyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0322] Prepared from1-[S-(2-pyridyl)-D-cysteinyl]-4-(1-methylpiperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 1.

[0323]¹H NMR.

[0324] ES-MS, m/z 506.3 (M+1)⁺.

[0325] Analysis for C₂₈H₃₅N₅O₂S.−1.2 HCl 1.4H₂O: Calcd: C 58.52; H 6.84;N 12.19; Cl 7.40; Found: C 58.61; H 6.64; N 12.06; Cl 7.24.

[0326] Analytical HPLC (Method 4): >99%, t_(r)=12.1 min.

Example 15

[0327]1-[N-(Indole-6-carbonyl)-S-(2-propyl)-D-cysteinyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0328] Prepared from1-[S-(2-propyl)-D-cysteinyl]-4-(1-methyl-piperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 1.

[0329]¹H NMR.

[0330] ES-MS, m/z 471.3 (M+1)⁺.

[0331] Analysis for C₂₆H₃₈N₄O₂S.1.2 HCl 1.0H₂O: Calcd: C 58.65; H 7.80;N 10.52; Cl 7.99; Found: C 58.65; H 7.68; N 10.49; Cl 7.80.

[0332] Analytical HPLC (Method 4): >98%, t_(r)=12.9 min.

Example 16

[0333]1-[N-(Indole-6-carbonyl)-S-methyl-D-cysteinyl]-4-(1-methyl-piperidin-4-yl)piperidineHydrochloride.

[0334] Prepared from1-(S-methyl-D-cysteinyl)-4-(1-methyl-piperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 3.

[0335]¹H NMR.

[0336] ES-MS, m/z 443.2 (M+1)⁺.

[0337] Analysis for C₂₄H₃₄N₄O₂S.1.0 HCl.0.8H₂O: Calcd: C 58.41; H 7.48;N 11.35; Cl 7.18; Found: C 58.33; H 7.31; N 11.14; Cl 7.06.

[0338] Analytical HPLC (Method 2): >98%, t_(r)=18.7 min.

Example 17

[0339]1-[N-(5-Chloroindole-2-carbonyl)-S-methyl-D-cysteinyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0340] Prepared from1-(S-methyl-D-cysteinyl)-4-(1-methyl-piperidin-4-yl)piperidine and5-chloroindole-2-carboxylic acid using methods substantially equivalentto General Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 1.

[0341]¹H NMR.

[0342] ES-MS, m/z 477.2 (M+1)⁺.

[0343] Analysis for C₂₄H₃₃N₄O₂SCl.1.0 HCl0.8H₂O: Calcd: C 54.60; H 6.80;N 10.61; Cl 13.43; Found: C 54.70; H 6.60; N 10.49; Cl 13.30.

[0344] Analytical HPLC (Method 3): >92%, t_(r)=22.2 min.

Example 18

[0345]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-S-methyl-D-cysteinyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0346] Prepared from1-(S-methyl-D-cysteinyl)-4-(1-methyl-piperidin-4-yl)piperidine and6-chlorobenzo[b]thiophene-2-carboxylic acid using methods substantiallyequivalent to General Coupling Method 1. The HCl salt is preparedfollowing General Salt Formation Method 1.

[0347]¹H NMR.

[0348] ES-MS, m/z 494.2 (M+1)⁺.

[0349] Analysis for C₂₄H₃₂N₃O₂S₂Cl.1.0 HCl0.8H₂O: Calcd: C 52.89; H6.40; N 7.71; Cl 13.01; Found: C 52.97; H 6.31; N 7.88; Cl 12.88.

[0350] Analytical HPLC (Method 3): >97%, t_(r)=23.6 min.

Example 19

[0351]1-[N-(Indole-6-carbonyl)-β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0352] Prepared from1-[β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineand indole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 1.

[0353]¹H NMR.

[0354] ES-MS, m/z 482.1 (M+1)⁺.

[0355] Analysis For C₂₇H₃₉N₅O₃.1.1 HCl.1.0H₂O: Calcd: C 60.08; H 7.86; N12.98; Cl 7.23; Found: C 60.19; H 8.17; N 12.76; Cl 7.11.

[0356] Analytical HPLC (Method 3): >99%, t_(r)=11.8 min.

Example 20

[0357]1-[N-(5-Chloroindole-2-carbonyl)-β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0358] Prepared from1-[β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineand 5-chloroindole-2-carboxylic acid using methods substantiallyequivalent to General Coupling Method 1. The HCl salt is preparedfollowing General Salt Formation Method 1.

[0359]¹H NMR.

[0360] ES-MS, m/z 516.3 (M+1)⁺.

[0361] Analysis for C₂₇H₃₈N₅O₃Cl.1.1 HCl.2.0H₂O: Calcd: C 54.76; H 7.34;N 11.83; Cl 12.57; Found: C 54.81; H 6.85; N 11.88; Cl 12.78.

[0362] Analytical HPLC (Method 3): >94%, t_(r)=15.5 min.

Example 21

[0363]1-[N-(3-Chloroindole-6-carbonyl)-P-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0364] Prepared from1-[β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineand 3-chloroindole-6-carboxylic acid using methods substantiallyequivalent to General Coupling Method 1. The HCl salt is preparedfollowing General Salt Formation Method 1.

[0365]¹H NMR.

[0366] ES-MS, m/z 516.3 (M+1)⁺.

[0367] Analysis For C₂₇H₃₈N₅O₃Cl.1.0 HCl.1.8H₂O: Calcd: C 55.44; H 7.34;N 11.97; Cl 12.12. Found: C 55.38; H 6.95; N 11.92; Cl 12.30.

[0368] Analytical HPLC (Method 3): >96%, t_(r)=13.4 min.

Example 22

[0369]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0370] Prepared from1-[β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineand 6-chlorobenzo[b]thiophene-2-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following General Salt Formation Method 1.

[0371]¹H NMR.

[0372] ES-MS, m/z 533.3 (M+1)⁺.

[0373] Analysis for C₂₇H₃₇N₄O₃SCl.1.5 HCl.1.3H₂O: Calcd: C 53.05; H6.78; N 9.17; Cl 14.50; Found: C 52.99; H 6.31; N 8.97; Cl 14.54.

[0374] Analytical HPLC (Method 3): >96%, t_(r)=16.6 min.

Example 23

[0375]1-[N-(Indole-6-carbonyl)-β-dimethylamino-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0376] Prepared from1-[β-dimethylamino-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidine andindole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 1.

[0377]¹H NMR.

[0378] ES-MS, m/z 440.3 (M+1)⁺.

[0379] Analysis For C₂₅H₃₇N₅O₂.1.0 HCl.2.2H₂O: Calcd: C 58.23; H 8.29; N13.58; Found: C 58.19; H 8.06; N 13.52.

[0380] Analytical HPLC (Method 3): >99%, t_(r)=9.5 min.

Example 24

[0381]1-[N-(5-Chloroindole-2-carbonyl)-β-dimethylamino-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0382] Prepared from1-[β-dimethylamino-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidine and5-chloroindole-2-carboxylic acid using methods substantially equivalentto General Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 1.

[0383]¹H NMR.

[0384] ES-MS, m/z 474.3 (M+1)⁺.

[0385] Analysis for C₂₅H₃₆N₅O₂Cl.1.2 HCl.1.7H₂O: Calcd: C 54.75; H 7.46;N 12.77; Found: C 55.01; H 7.07; N 12.40.

[0386] Analytical HPLC (Method 3): >98%, t_(r)=15.8 min.

Example 25

[0387]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-β-dimethylamino-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0388] Prepared from1-[β-dimethylamino-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidine and6-chlorobenzo[b]thiophene-2-carboxylic acid using methods substantiallyequivalent to General Coupling Method 1. The HCl salt is preparedfollowing General Salt Formation Method 1.

[0389]¹H NMR.

[0390] ES-MS, m/z 491.2 (M+1)⁺.

[0391] Analysis For C₂₅H₃₅N₄O₂SCl.1.2 HCl.1.5H₂O: Calcd: C 53.44; H7.03; N 9.97; Found: C 53.20; H 6.64; N 9.80.

[0392] Analytical HPLC (Method 3): >99%, t_(r)=16.7 min.

Example 26

[0393]1-[N-(5-Chloroindole-2-carbonyl)-β-(1-imidazolyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineTrihydrochloride.

[0394] Prepared from1-[β-(1-imidazolyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidine and5-chloroindole-2-carboxylic acid using methods substantially equivalentto General Coupling Method 1. Purification by the reverse phasechromatography option gives the hydrochloride salt.

[0395]¹H NMR.

[0396] ES-MS, m/z 497.2 (M+1)⁺.

[0397] Analysis for C₂₆H₃₃N₆O₂Cl.3.0 HCl.1.0H₂O: Calcd: C 50.01; H 6.13;N 13.46; Found: C 49.64; H 5.75; N 12.24.

[0398] Analytical HPLC (Method 3): >99%, t_(r)=16.1 min.

Example 27

[0399]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-β-(1-imidazol-yl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineDihydrochloride.

[0400] Prepared from1-[β-(1-imidazolyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidine and6-chlorobenzo[b]thiophene-2-carboxylic acid using methods substantiallyequivalent to General Coupling Method 1. Purification by the reversephase chromatography option gives the hydrochloride salt.

[0401]¹H NMR.

[0402] ES-MS, m/z 514.2 (M+1)⁺.

[0403] Analysis for C₂₆H₃₂N₅O₂SCl.2.0 HCl.3.3H₂O: Calcd: C 48.31; H6.33; N 10.83; Found: C 48.51; H 5.94; N 10.15.

[0404] Analytical HPLC (Method 3): >99%, t_(r)=17.0 min.

Example 28

[0405]1-[N-(5-Chloroindole-2-carbonyl)-β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineDihydrochloride.

[0406] Prepared from1-[β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineand 5-chloroindole-2-carboxylic acid using methods substantiallyequivalent to General Coupling Method 1. Purification by the reversephase chromatography option gives the dihydrochloride salt.

[0407]¹H NMR.

[0408] ES-MS, m/z 514.3 (M+1)⁺.

[0409] Analysis for C₂₈H₄₀N₅O₂Cl.2.1 HCl.5.0H₂O: Calcd: C 49.40; H 7.71;N 10.29; Found: C 49.74; H 7.59; N 9.59.

[0410] Analytical HPLC (Method 3): >99%, t_(r)=17.0 min.

Example 29

[0411]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineHydrochloride.

[0412] Prepared from1-[β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperidineand 6-chlorobenzo[b]thiophene-2-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following General Salt Formation Method 1.

[0413]¹H NMR.

[0414] ES-MS, m/z 531.3 (M+1)⁺.

[0415] Analysis for C₂₈H₃₉N₄O₂SCl.1.0 HCl.0.9H₂O: Calcd: C 57.60; H7.22; N 9.60; Found: C 57.56; H 7.02; N 9.41.

[0416] Analytical HPLC (Method 3): >99%, t_(r)=18.5 min.

Preparation of Compounds of Formula (IX), X¹═N

[0417]1-(N-Boc-D-allo-Threoninyl)-4-(1-methylpiperidin-4-yl)-piperazine.

[0418] Prepared from N-Boc-D-allo-threonine and1-(1-methyl-piperidin-4-yl)piperazine using methods substantiallyequivalent to General Coupling Method 1.

[0419]¹H NMR.

[0420] ES-MS, m/z 385.5 (M+1)⁺.

[0421] Analysis For C₁₉H₃₆N₄O₄.1.0H₂O: Calcd: C 56.69; H 9.52; N 13.92;Found: C 57.18; H 9.59; N 13.85.

[0422]1-(N-Boc-O-Methyl-D-allo-threoninyl)-4-(1-methylpiperidin-4-yl)piperazine.

[0423] Prepared from N-Boc-O-methyl-D-allo-threonine and1-(1-methylpiperidin-4-yl)piperazine using methods substantiallyequivalent to General Coupling Method 1.

[0424]¹H NMR.

[0425] ES-MS, m/z 398.8 (M+1)⁺.

[0426] 1-(N-Boc-D-Serinyl)-4-(1-methylpiperidin-4-yl)piperazine.

[0427] Prepared from N-Boc-D-serine and1-(1-methylpiperidin-4-yl)piperazine using methods substantiallyequivalent to General Coupling Method 1.

[0428]¹H NMR.

[0429] ES-MS, m/z 371.2 (M+1)⁺.

[0430] Analysis For C₁₈H₃₄N₄O₄.0.2H₂O: Calcd: C 56.88; H 9.02; N 14.74;Found: C 57.02; H 9.05; N 14.43.

[0431] 1-(N-Boc-D-Methioninyl)-4-(1-methylpiperidin-4-yl)-piperazine.

[0432] Prepared from N-Boc-D-methionine and1-(1-methyl-piperidin-4-yl)piperazine using methods substantiallyequivalent to General Coupling 4.

[0433] ES-MS, m/z 415.3 (M+1)⁺.

[0434]1-[N-Boc-β-(4-Morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazine.

[0435] Prepared from N-Boc-β-(4-morpholinyl)-D-alanine potassium saltand 1-(1-methylpiperidin-4-yl)piperazine using methods substantiallyequivalent to General Coupling Method 1.N-Boc-β-(1-morpholinyl)-D-alanine potassium salt is prepared fromBoc-D-serine P-lactone and N-trimethylsilylmorpholine using methodssubstantially equivalent to General Lactone Opening Method 2.

[0436]¹H NMR.

[0437] ES-MS, m/z 440.3 (M+1)⁺.

[0438]1-[N-Boc-β-(1-Piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazine.

[0439] Prepared from N-Boc-β-(1-piperidinyl)-D-alanine potassium saltand 1-(1-methylpiperidin-4-yl)piperazine using methods substantiallyequivalent to General Coupling Method 1.N-Boc-β-(1-piperidinyl)-D-alanine potassium salt is prepared fromBoc-D-serine P-lactone and 1-(trimethylsilyl)piperidine using methodssubstantially equivalent to General Lactone Opening Method 2.

[0440]¹H NMR.

[0441] ES-MS, m/z 438.3 (M+1)⁺.

Preparation of Compounds of Formula (IV), X¹═N

[0442] 1-(D-allo-Threoninyl)-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0443] Prepared from1-(N-Boc-D-allo-threoninyl)-4-(1-methyl-piperidin-4-yl)piperazine usingmethods substantially equivalent to those described in GeneralDeprotection Method 2.

[0444]¹H NMR.

[0445] ES-MS, m/z 285.4 (M+1)⁺.

[0446] Analysis for C₁₄H₂₈N₄O₂.3.0 HCl: Calcd: C 42.70; H 7.94; N 14.23;Cl 27.01; Found: C 42.29; H 7.84; N 14.26; Cl 26.84.

[0447]1-(O-Methyl-D-allo-threoninyl)-4-(1-methylpiperidin-4-yl)-piperazineHydrochloride.

[0448] Prepared from1-(N-Boc-O-methyl-D-allo-threoninyl)-4-(1-methylpiperidin-4-yl)piperazineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0449]¹H NMR.

[0450] ES-MS, 299.4 m/z (M+1)⁺.

[0451] 1-(D-Serinyl)-4-(1-methylpiperidin-4-yl)piperazine Hydrochloide.

[0452] Prepared from1-(N-Boc-D-serinyl)-4-(1-methylpiperidin-4-yl)piperazine using methodssubstantially equivalent to those described in General DeprotectionMethod 2.

[0453]¹H NMR.

[0454] ES-MS, m/z 271.4 (M+1)⁺.

[0455] Analysis For C₁₃H₂₆N₄O₂.3.0 HCl.1.0H₂O: Calcd: C 39.25; H 7.86; N14.09; Cl 26.74; Found: C 39.69; H 7.52; N 14.25; Cl 27.35.

[0456] 1-(D-Methioninyl)-4-(1-methylpiperidin-4-yl)piperazine.

[0457] Prepared from1-(N-Boc-D-methioninyl)-4-(1-methyl-piperidin-4-yl)piperazine usingmethods substantially equivalent to those described in GeneralDeprotection Method 1.

[0458] ES-MS, m/z 315.2 (M+1)⁺.

[0459]1-[β-(4-Morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)-piperazineHydrochloride.

[0460] Prepared from1-[N-Boc-β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0461]¹H NMR.

[0462] ES-MS, m/z 340.3 (M+1)⁺.

[0463]1-[β-(1-Piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)-piperazineHydrochloride.

[0464] Prepared from1-[N-Boc-β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineusing methods substantially equivalent to those described in GeneralDeprotection Method 2.

[0465]¹H NMR.

[0466] ES-MS, m/z 338.3 (M+1)⁺.

EXAMPLES X¹═N Example 30

[0467]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-D-allo-threoninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0468] Prepared from1-(D-allo-threoninyl)-4-(1-methyl-piperidin-4-yl)piperazinehydrochloride and 6-chlorobenzo[b]thiophene-2-carboxylic acid usingmethods substantially equivalent to General Coupling Method 1. The finalcrude product is treated with aqueous 0.2 N HCl and purified viaprep-HPLC (80:20 to 40:60 0.01% HCl in water:acetonitrile).

[0469]¹H NMR.

[0470] ES-MS, m/z 479.3 (M+1)⁺; 477.4 (M−1)⁻.

[0471] Analysis for C₂₃H₃₁ClN₄O₃S.1.1HCl.3.3H₂O: Calcd: C 47.74; H 6.74;N 9.68; Found: C 47.31; H 6.01; N 9.66.

[0472] Analytical HPLC (Method 1): >99%, t_(r)=22.1 min.

Example 31

[0473]1-[N-(5-Chloroindole-2-carbonyl)-D-allo-threoninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0474] Prepared from1-(D-allo-threoninyl)-4-(1-methyl-piperidin-4-yl)piperazinehydrochloride and 5-chloroindole-2-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following Salt Formation Method 1. The final crude product istreated with aqueous 0.2 N HCl and purified via prep-HPLC (80:20 to40:60 0.01% HCl in water:acetonitrile).

[0475]¹H NMR.

[0476] ES-MS, m/z 462.2 (M+1)⁺; 460.2 (M−1)⁻.

[0477] Analysis for C₂₃H₃₂ClN₅O₃.1.1 HCl.4.50H₂O: Calcd: C 47.37; H7.28; N 12.01; Found: C 47.27; H 6.37; N 11.95.

[0478] Analytical HPLC (Method 1): >96%, t_(r)=21.0 min.

Example 32

[0479]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-O-methyl-D-allo-threoninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0480] Prepared from1-(O-methyl-D-allo-threoninyl)-4-(1-methylpiperidin-4-yl)piperazinehydrochloride and 6-chlorobenzo[b]thiophene-2-carboxylic acid usingmethods substantially equivalent to General Coupling Method 1. The HClsalt is prepared following Salt Formation Method 1.

[0481]¹H NMR.

[0482] ES-MS, m/z 493.1 (M+1)⁺; 491.2 (M−1)⁻.

[0483] Analysis for C₂₃H₃₁ClN₄O₃S.1.0 HCl1.0H₂O: Calcd: C 51.78; H 6.42;N 10.50; Found: C 51.93; H 7.02; N 10.28.

[0484] Analytical HPLC (Method 1): >96%, t_(r)=22.8 min.

Example 33

[0485]1-[N-(5-Chloroindole-2-carbonyl)-O-methyl-D-allo-threoninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0486] Prepared from1-(O-methyl-D-allo-threoninyl)-4-(1-methylpiperidin-4-yl)piperazinehydrochloride and 5-chloroindole-2-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following Salt Formation Method 1.

[0487]¹H NMR.

[0488] ES-MS, m/z 476.1 (M+1)⁺; 474.2 (M−1)⁻.

[0489] Analytical HPLC (Method 1): >96%, t_(r)=21.4 min.

Example 34

[0490]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-D-serinyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0491] Prepared from 1-(D-serinyl)-4-(1-methylpiperidin-4-yl)-piperazinehydrochloride and 6-chlorobenzo[b]thiophene-2-carboxylic acid usingmethods substantially equivalent to General Coupling Method 1. The HClsalt is prepared following Salt Formation Method 1.

[0492]¹H NMR.

[0493] ES-MS, m/z 465.1 (M+1)⁺; 463.1 (M−1)⁻.

[0494] Analysis for C₂₂H₂₉ClN₄O₂S.1.3 HCl.3.3H₂O: Calcd: C 49.26; H6.93; N 10.45; Found: C 48.98; H 6.27; N 10.72.

[0495] Analytical HPLC (Method 1): >99%, t_(r)=18.9 min.

Example 35

[0496]1-[N-(5-Chloroindole-2-carbonyl)-D-serinyl]-4-(1-methyl-piperidin-4-yl)piperazineHydrochloride.

[0497] Prepared from 1-(D-serinyl)-4-(1-methylpiperidin-4-yl)-piperazinehydrochloride and 5-chloroindole-2-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following Salt Formation Method 1.

[0498]¹H NMR.

[0499] ES-MS, m/z 448.2(M+1)⁺; 446.2(M−1)⁻.

[0500] Analysis For C₂₂H₃₀ClN₅O₂.1.1 HCl.3.0H₂O Calcd: C 47.74; H 6.90;N 12.92; Found: C 48.47; H 6.18; N 12.70.

[0501] Analytical HPLC (Method 1): >99%, t_(r)=18.9 min.

Example 36

[0502]1-[N-(Indole-6-carbonyl)-D-serinyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0503] Prepared from 1-(D-serinyl)-4-(1-methylpiperidin-4-yl)-piperazinehydrochloride and indole-6-carboxylic acid using methods substantiallyequivalent to General Coupling Method 1. The HCl salt is preparedfollowing General Salt Formation Method 1.

[0504]¹H NMR.

[0505] ES-MS, m/z 448.2 (M+1)⁺; 446.2 (M−1)⁻.

[0506] Analysis for C₂₂H₃₀ClN₅O₃.1.1 HCl3.0H₂O: Calcd: C 48.74; H 6.91;N 12.98; Found: C 48.47; H 6.18; N 12.70.

[0507] Analytical HPLC (Method 1): >99%, t_(r)=18.9 min.

Example 37

[0508]1-[N-(4-Methoxybenzoyl)-D-methioninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0509] Prepared from1-(D-methioninyl)-4-(1-methylpiperidin-4-yl)piperazine hydrochloride and4-methoxybenzoic acid using methods substantially equivalent to GeneralCoupling Method 4. The HCl salt is prepared following General SaltFormation Method 2.

[0510]¹H NMR.

[0511] ES-MS, m/z 449.2 (M+1)⁺.

[0512] Analysis for C₂₃H₃₆N₄O₃.1.8 HCl 1.2H₂O: Calcd: C 51.55; H 7.56; N10.45; Cl 11.91; Found: C 51.23; H 7.28; N 10.16; Cl 12.39.

[0513] Analytical HPLC (Method 1): 98%, t_(r)=14.4 min.

Example 38

[0514]1-[N-(Indole-6-carbonyl)-D-methioninyl]-4-(1-methyl-piperidin-4-yl)piperazineHydrochloride.

[0515] Prepared from1-(D-methioninyl)-4-(1-methylpiperidin-4-yl)piperazine hydrochloride and6-indole carboxylic acid using methods substantially equivalent toGeneral Coupling Method 4. The HCl salt is prepared following GeneralSalt Formation Method 2.

[0516]¹H NMR.

[0517] ES-MS, m/z 449.2 (M+1)⁺.

[0518] Analysis for C₂₃H₃₆N₄O₃.1.8 HCl.1.2H₂O: Calcd: C 51.55; H 7.56; N10.45; Cl 11.91; Found: C 51.23; H 7.28; N 10.16; Cl 12.39.

[0519] Analytical HPLC (Method 1): 98%, t_(r)=14.4 min.

Example 39

[0520] 1-[N—(Indole-6-carbonyl)-β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0521] Prepared from1-[β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineand indole-6-carboxylic acid using methods substantially equivalent toGeneral Coupling Method 1. The HCl salt is prepared following GeneralSalt Formation Method 1.

[0522]¹H NMR.

[0523] ES-MS, m/z 483.3 (M+1)⁺.

[0524] Analysis for C₂₆H₃₈N₆O₃.1.6 HCl.1.3H₂O: Calcd: C 55.33; H 7.54; N14.89; Found: C 55.38; H 7.15; N 14.98.

[0525] Analytical HPLC (Method 3): >99%, t_(r)=11.7 min.

Example 40

[0526]1-[N-(5-Chloroindole-2-carbonyl)-P-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0527] Prepared from1-[β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineand 5-chloroindole-2-carboxylic acid using methods substantiallyequivalent to General Coupling Method 1. The HCl salt is preparedfollowing General Salt Formation Method 1.

[0528]¹H NMR.

[0529] ES-MS, m/z 517.3 (M+1)⁺.

[0530] Analysis for C₂₆H₃₇N₆O₃Cl 1.0 HCl.1.5H₂O: Calcd: C 53.79; H 7.12;N 14.48.

[0531] Found: C 53.52; H 6.89; N 14.18.

[0532] Analytical HPLC (Method 3): >99%, t_(r)=10.7 min.

Example 41

[0533]1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0534] Prepared from1-[β-(4-morpholinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl) piperazineand 6-chlorobenzo[b]thiophene-2-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following General Salt Formation Method 1.

[0535]¹H NMR.

[0536] ES-MS, m/z 534.2 (M+1)⁺.

[0537] Analysis for C₂₆H₃₆N₅O₃SCl.1.0 HCl.1.7H₂O: Calcd: C 51.94; H6.77; N 11.65; Found: C 51.98; H 6.58; N 11.62.

[0538] Analytical HPLC (Method 3): >99%, t_(r)=12.7 min.

Example 42

[0539]1-[N-(5-Chloroindole-2-carbonyl)-β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0540] Prepared from1-[β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineand 5-chloroindole-2-carboxylic acid using methods substantiallyequivalent to General Coupling Method 1. Purification by the reversephase chromatography option gives the hydrochloride salt.

[0541]¹H NMR.

[0542] ES-MS, m/z 515.3 (M+1)⁺. Analysis for C₂₇H₃₉N₆O₂Cl.3.3HCl.1.8H₂O: Calcd: C 48.56; H 6.93; N 12.58.

[0543] Found: C 48.50; H 6.55; N 11.58.

[0544] Analytical HPLC (Method 3): >97%, t_(r)=12.8 min.

Example 43

[0545] 1-[N-(6-Chlorobenzo[b]thiophene-2-carbonyl)-β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl)piperazineHydrochloride.

[0546] Prepared from1-[β-(1-piperidinyl)-D-alaninyl]-4-(1-methylpiperidin-4-yl) piperazineand 6-chlorobenzo[b]thiophene-2-carboxylic acid using methodssubstantially equivalent to General Coupling Method 1. The HCl salt isprepared following General Salt Formation Method 1.

[0547]¹H NMR.

[0548] ES-MS, m/z 532.3 (M+1)⁺.

[0549] Analysis For C₂₇H₃₈N₅O₂SCl.1.0 HCl.1.8H₂O: Calcd: C 53.95; H7.14; N 11.65; Found: C 54.11; H 6.90; N 11.26.

[0550] Analytical HPLC (Method 3): >99%, t_(r)=14.5 min.

[0551] Enzyme Inhibition assays:

[0552] The ability of a test compound to inhibit factor Xa may beevaluated in one or more of the following Enzyme Inhibition assays, orin other standard assays known to those skilled in the art.

[0553] Enzyme Inhibition Assay

[0554] Human factor Xa and human thrombin are purchased from EnzymeResearch Laboratories (South Bend, Ind., USA). Other proteases are fromother commercial sources. Chromogenic para-nitroanilide peptide proteasesubstrates are purchased from Midwest Biotech (Fishers, Ind., USA).

[0555] The binding affinities for human factor Xa are measured asapparent association constants (Kass) derived from protease inhibitionkinetics as described previously. a,b,c,d The apparent Kass values areobtained using automated (BioMek-1000) dilutions of inhibitors (Kassdeterminations are performed in triplicate at each of four-eightinhibitor concentrations) into 96-well plates and chromogenic substratehydrolysis rates determined at 405 nm using a Thermomax plate readerfrom Molecular Devices (San Francisco). For factor Xa inhibition, theassay protocol is: 50 μL buffer (0.06 M tris, 0.3 M NaCl, pH 7.4); 25 μLinhibitor test solution (in MeOH); 25 μL human factor Xa (32 nM in 0.03M tris, 0.15 M NaCl, 1 mg/mL HSA); finally, 150 μL BzIleGluGlyArgpNA(0.3 mM in water) added within 2 min to start hydrolysis. Final [factorXa] is 3.2 nM. [Free Xa] and [bound Xa] are determined from linearstandard curves on the same plate by use of SoftmaxPro software for eachinhibitor concentration and apparent Kass calculated for each inhibitorconcentration which produced hydrolysis inhibition between 20% and 80%of the control (3.2 nM factor Xa): apparentKass=[E:I]/[E_(f)][I_(f)]=[E_(b)]/[E_(f)][I^(O)-I_(b)]. The apparentKass values so obtained are approximately the inverse of the Ki for therespective inhibitors [1/appKass=app Ki]. The variability of meanapparent Kass values determined at the single substrate concentration is+/−15%. The assay system Km was measured as 0.347+/−0.031 mM [n=4]; andVmax was 13.11+/−0.76 μM/min.

[0556] Kass values are determined with thrombin and other proteasesusing the same protocol with the following enzyme and substrateconcentrations:

[0557] thrombin, 5.9 nM with 0.2 mM BzPheValArgpNA;

[0558] factor XIa, 1.2 nM with 0.4 mM pyroGluProArgpNA;

[0559] factor XIIa, 10 nM with 0.2 mM HDProPheArgpNA;

[0560] plasmin, 3.4 nM with 0.5 mM HDValLeuLyspNA;

[0561] nt-PA, 1.2 nM with 0.8 mM HDIleProArgpNA;

[0562] urokinase, 0.4 nM with 0.4 mM pyroGluGlyArgpNA;

[0563] aPC, 3 nM with 0.174 mM pyroGluProArgpNA;

[0564] plasma kallikrein, 1.9 nM with D-ProPheArgpNA; and

[0565] bovine trypsin, 1.4 nM with 0.18 mM BzPheValArgpNA.

CITATIONS

[0566] (a) Sall D J, J A Bastian, S L Briggs, J A Buben, N.Y. Chirgadze,D K Clawson, M L Denny, D D Giera, D S Gifford-Moore, R W Harper, K LHauser, V J Klimkowski, T J Kohn, H-S Lin, J R McCowan, A D Palkowitz, GF Smith, M E Richett, K Takeuchi, K J Thrasher, J M Tinsley, B GUtterback, S-C B Yan, M Zhang. Dibasic Benzo[b]thiophenes Derivatives asa Novel Class of Active Site Directed Thrombin Inhibitors. 1.Determination of the Serine Protease Selectivity, Structure-ActivityRelationships and Binding Orientation. J Med Chem 40 3489-3493 (1997).

[0567] (b) Smith G F, T J Craft, D S Gifford-Moore, W J Coffman, K DKurz, E Roberts, R T Shuman, G E Sandusky, N.Dak. Jones, N Chirgadze,and C V Jackson. A Family of Arginal Thrombin Inhibitors Related toEfegatran. Sem. Thrombos. Hemost. 22, 173-183 (1996).

[0568] (c) Smith G F, D S Gifford-Moore, T J Craft, N Chirgadze, K JRuterbories, T D Lindstrom, J H Satterwhite. Efegatran: A NewCardiovascular Anticosagulant. In New Anticoagulants for theCardiovascular Patient. Ed. R Pifarre. Hanley & Belfus, Inc.,Philadelphia (1997) pp 265-300.

[0569] (d) Sall D J, D L Bailey, J A Bastian, N.Y. Chirgadze, A CClemens-Smith, M L Denney, M J Fisher, D D Geira, D S Gifford-Moore, R WHarper, L M Johnson, V J Klimkowski, T J Kohn, H S Lin, J R McCowan, A DPalkowitz, Me. Richett, G F Smith, D W Snyder, K Takeuchi, J E Toth, MZang. Diamino Benzo[b]thiophene Derivatives as a Novel Class of ActiveSite Directed Thrombin Inhibitors: 5. Potency, Efficacy andPharmacokinetic Properties of Modified C-3 Side Chain Derivatives. J.Med. Chem., 43, 649-663 (2000).

[0570] The compounds of formula (I) exemplified herein have been foundto exhibit a Kass of greater than 1×10⁶ L/mole in the enzyme inhibitionassay. For example, the compounds, or their pharmaceutically acceptablesalts, exemplified herein have been to exhibit Kass values of greaterthan 1×10⁶ L/mole.

[0571] The ability of a test compound to elongate Partial ThromboplastinTime (Prothrombin Time) may be evaluated in the following testprotocols.

[0572] Partial Thromboplastin Time (Prothrombin) Test Protocol

[0573] Venous blood is collected into 3.2% (0.109 M) trisodium citratevacutainer tubes at 1 volume of anticoagulant to nine volumes of blood.The blood cells are separated by centrifugation at 700 g for ten minutesto yield plasma, which is frozen at 70° C. until required.

[0574] To perform the test, 100 μL of plasma are pipetted into in aglass test tube, 1 μL of test compound in DMSO is added, and allowed towarm to 37° over two minutes. 100 μL of warm (37°) Manchester (tissuethromboplastin) reagent (Helena Biosciences, UK) is added, allowed toequilibrate for two minutes. 100 μL of warm (37°) 25 mM calcium chloridesolution is added to initiate clotting. The test tube is tilted threetimes through a 90° angle every five seconds to mix the reagents and thetime to clot formation recorded. Data from a series of observations andtest compound concentrations are analysed by a SAS statistical analysisprogram and a CT2 (Concentration required to double clotting time) foreach compound is generated.

[0575] Compounds of the invention have been found to significantlyelongate the partial thromboplastin time (Prothrombin time).

[0576] Alternative Prothrombin Time and APTT Protocols

[0577] Coagulation Determinations: Prothrombin Times and APTT values aredetermined in HUMAN PLASMA with a STA instrument (Stago). BioPT is aspecial non-plasma clotting assay triggered with human tissue factor(Innovin). Possible binding to albumen or to lipid are assessed bycomparing the BioPT effects in the presence/absence of 30 mg/mL humanalbumen (HSA) and 1 mg/mL phosphatidyl choline (PC). Inhibitors aredelivered in 50% aqueous methanol vehicle.

[0578] APTT ASSAY

[0579] 75 μL plasma Citrol Baxter-Dade Citrated Normal Human Plasma

[0580] 25 μL test solution

[0581] 75 μL Actin Baxter-Dade Activated Cephaloplastin incubate 2 minmin. @ 37° C.

[0582] 75 μl CaCl₂ (0.02 M)

[0583] PT ASSAY

[0584] 75 μL plasma

[0585] 25 μL test solution

[0586] 75 μL saline incubate 1 min. @ 37° C.

[0587] 75 μL Innovin Baxter-Dade Recombinant Human Tissue Factor

1. A compound of formula (I)

in which x¹ represents CH or N; n is 1 or 2; each R represents hydrogenor methyl; R¹ represents imidazol-1-yl or X^(a)R^(a) in which X^(a)represents O, S or NR^(b); R^(a) represents a hydrogen atom, a(1-4C)alkyl group, a phenyl group or a pyridyl group; R^(b) represents ahydrogen atom, a (1-4C)alkyl group or, together with R^(a) and thenitrogen atom to which they are attached represents a saturated 4 to6-membered ring which may contain, as a ring member, one of O, S andNR^(c) in which R^(c) represents hydrogen or (1-4C)alkyl; and R² isselected from

in which X² represents a hydrogen atom, a halogen atom or an aminogroup; X³ represents a hydrogen atom, a methyl group, a fluorine atom, achlorine atom or a bromine atom; X⁴ represents a hydrogen atom, a methylgroup or a halogen atom; X⁵ represents a chlorine atom, a methoxy groupor a methyl group; and X⁶ represents a hydrogen atom, a halogen atom ora methyl group; or a pharmaceutically acceptable salt thereof.
 2. Acompound as claimed in claim 1, in which (CHR)_(n) is selected from CH₂,CHCH₃ and CH₂CH₂.
 3. A compound as claimed in claim 1, in which R¹represents imidazol-1-yl, hydroxy, (1-4C)alkoxy, (1-4C)alkylthio,di(1-4C)alkylamino, phenylthio, pyridylthio, piperidin-1-yl ormorpholino.
 4. A compound as claimed in claim 3, in which R¹ representsimidazol-1-yl, hydroxy, methoxy, methylthio, 2-propylthio,dimethylamino, phenylthio, pyrid-2-ylthio, piperidin-1-yl or morpholino.5. A compound as claimed in claim 4, in which (CHR)_(n)R₁ representsimidazol-1-ylmethyl, hydroxymethyl, 1-hydroxyethyl, methoxymethyl,1-methoxyethyl, methylthiomethyl, prop-2-ylthiomethyl,2-methylthioethyl, N,N-dimethylaminomethyl, phenylthiomethyl,pyrid-2-ylthiomethyl, piperidin-1-ylmethyl or morpholinomethyl.
 6. Acompound as claimed in claim 1, in which X² represents a hydrogen atomor a halogen atom.
 7. A compound as claimed in claim 6, in which X²represents a hydrogen atom or a fluorine atom; X³ represents a hydrogenatom, a fluorine atom, a chlorine atom or a methyl group; X⁴ representsa chlorine atom; X⁵ represents a chlorine atom or a methoxy group; andX⁶ represents a chlorine atom.
 8. A compound as claimed in claim 6, inwhich R² is 4-chlorophenyl, 4-methoxyphenyl, 3-fluoro-4-methoxyphenyl,indol-6-yl, 3-methylindol-6-yl, 3-chloroindol-6-yl, 5-fluoroindol-2-yl,5-chloroindol-2-yl or 6-chlorobenzo[b]-thiophen-2-yl.
 9. A compound asclaimed in claim 8, in which R² is 4-methoxyphenyl, indol-6-yl or5-chloroindol-2-yl.
 10. A compound as claimed in any one of claims 1 to9, in which X¹ represents CH.
 11. A compound as claimed in any one ofclaims 1 to 9, in which X¹ represents N.
 12. A pharmaceuticalcomposition, which comprises a compound as claimed in claim 1, togetherwith a pharmaceutically acceptable diluent or carrier.
 13. A process forpreparing a compound as claimed in claim 1, which comprises (a) reactinga compound of formula (II)

 or a salt thereof, with a compound of formula (III)

 or a reactive derivative thereof; or (b) reacting a compound of formula(IV)

 or a salt thereof, with a compound of formula (V) HOOC—R²  (V)  or asalt or reactive derivative thereof; followed, if a pharmaceuticallyacceptable salt is desired, by forming a pharmaceutically acceptablesalt.
 14. A compound of formula (III)

or a salt thereof, in which R, n, R¹ and R² are as defined in claim 1.15. A compound of formula (IV)

or a salt thereof, in which X¹, R, n, and R¹ are as defined in claim 1.16. (canceled)
 17. (canceled)
 18. A method of treating a thromboticdisorder in a subject requiring treatment, which comprises administeringan effective amount of a compound as claimed in claim
 1. 19. A compoundas claimed in claim 1, in which X¹ represents CH; (CHR)_(n)R₁ representsimidazol-1-ylmethyl, hydroxymethyl, 1-hydroxyethyl, methoxymethyl,1-methoxyethyl, methylthiomethyl, prop-2-ylthiomethyl,2-methylthioethyl, N,N-dimethylaminomethyl, phenylthiomethyl,pyrid-2-ylthiomethyl, piperidin-1-ylmethyl or morpholinomethyl; and R²is 4-chlorophenyl, 4-methoxyphenyl, 3-fluoro-4-methoxyphenyl,indol-6-yl, 3-methylindol-6-yl, 3-chloroindol-6-yl, 5-fluoroindol-2-yl,5-chloroindol-2-yl or 6-chlorobenzo[b]thiophen-2-yl.
 20. Apharmaceutical composition, which comprises a compound as claimed inclaim 19, together with a pharmaceutically acceptable diluent orcarrier.
 21. A method of treating a thrombotic disorder in a subjectrequiring treatment, which comprises administering an effective amountof a compound as claimed in claim
 19. 22. A compound as claimed in claim1, in which X¹ represents N; (CHR)_(n)R₁ represents imidazol-1-ylmethyl,hydroxymethyl, 1-hydroxyethyl, methoxymethyl, 1-methoxyethyl,methylthiomethyl, prop-2-ylthiomethyl, 2-methylthioethyl,N,N-dimethylaminomethyl, phenylthiomethyl, pyrid-2-ylthiomethyl,piperidin-1-ylmethyl or morpholinomethyl; and R² is 4-chlorophenyl,4-methoxyphenyl, 3-fluoro-4-methoxyphenyl, indol-6-yl,3-methylindol-6-yl, 3-chloroindol-6-yl, 5-fluoroindol-2-yl,5-chloroindol-2-yl or 6-chlorobenzo[b]thiophen-2-yl.
 23. Apharmaceutical composition, which comprises a compound as claimed inclaim 22, together with a pharmaceutically acceptable diluent orcarrier.
 24. A method of treating a thrombotic disorder in a subjectrequiring treatment, which comprises administering an effective amountof a compound as claimed in claim 22.